1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2005 Poul-Henning Kamp
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29
30 // Modified to support the Haiku FAT driver.
31
32 #ifdef FS_SHELL
33 #include "fssh_api_wrapper.h"
34 #else
35 #include <sys/stat.h>
36 #include <sys/types.h>
37 #endif
38
39 #include "sys/param.h"
40 #include "sys/systm.h"
41 #include "sys/buf.h"
42 #include "sys/mount.h"
43 #include "sys/namei.h"
44 #include "sys/vnode.h"
45
46 #include "fs/msdosfs/denode.h"
47 #include "fs/msdosfs/direntry.h"
48
49 #include "dosfs.h"
50
51
52 #ifdef USER
53 #define dprintf printf
54 #endif
55
56
57 /*! Determine the inode number for a direntry location and return the corresponding node if it is
58 constructed.
59 @param hash A tentative location-based inode.
60 @param arg Pointer to a pre-allocated uint64.
61 @param td Ignored in the port.
62 @param fn Ignored in the port. In FreeBSD, this is a function pointer that would be passed to
63 the VFS and applied to the VFS's list of vnodes to find a match.
64 @param arg Pointer to a pre-allocated uint64 that will be set to the final inode number.
65 @post *arg is set to the inode number corresponding to hash (which may or may not equal hash).
66 *vpp points to the corresponding BSD-style vnode, if that vnode already exists in memory. If
67 the node doesn't exist in memory, *vpp is set to NULL.
68 The function signature is modified to make hash a uint64 instead of uint32. This is consistent
69 with the type passed by deget, and protects against overflow.
70 This function never calls get_vnode when the node in question is not already registered with
71 the VFS, so it is suitable for use within dosfs_read_vnode.
72 */
73 int
vfs_hash_get(struct mount * mp,uint64 hash,int flags,thread_id td,struct vnode ** vpp,vfs_hash_cmp_t * fn,void * arg)74 vfs_hash_get(struct mount* mp, uint64 hash, int flags, thread_id td, struct vnode** vpp,
75 vfs_hash_cmp_t* fn, void* arg)
76 {
77 uint64* finalInode = arg;
78 status_t status = B_OK;
79 bool exists = false;
80 // Has a node with the same inode number already been constructed?
81
82 status = assign_inode(mp, (ino_t*)&hash);
83 if (status != B_OK)
84 return B_TO_POSIX_ERROR(status);
85
86 exists = node_exists(mp, hash);
87 if (exists == true) {
88 // get_vnode will just return a ref (without calling dosfs_read_vnode)
89 status = get_vnode(mp->mnt_fsvolume, hash, (void**)vpp);
90 if (status != B_OK) {
91 dprintf("FAT vfs_hash_get: get_vnode failure\n");
92 return B_TO_POSIX_ERROR(status);
93 }
94 rw_lock_write_lock(&(*vpp)->v_vnlock->haikuRW);
95 // the driver expects the node to be returned locked
96 } else {
97 // The node needs to be initialized. Returning with a NULL vpp will
98 // signal deget() to go through with setting it up.
99 *vpp = NULL;
100 }
101
102 *finalInode = hash;
103
104 return 0;
105 }
106
107
108 /*! In FreeBSD, this adds vp to a VFS-level list of nodes. In Haiku, the same thing is
109 taken care of automatically by get_vnode.
110 */
111 int
vfs_hash_insert(struct vnode * vp,uint64 hash,int flags,thread_id td,struct vnode ** vpp,vfs_hash_cmp_t * fn,void * arg)112 vfs_hash_insert(struct vnode* vp, uint64 hash, int flags, thread_id td, struct vnode** vpp,
113 vfs_hash_cmp_t* fn, void* arg)
114 {
115 ASSERT(node_exists(vp->v_mount, hash) == false);
116
117 // This tells the client that there is no existing vnode with the same
118 // inode number. This should always be the case under the conditions in which
119 // the FAT driver calls this function: if there was an existing node,
120 // deget would have returned early.
121 *vpp = NULL;
122
123 return 0;
124 }
125
126
127 /*! In FreeBSD, this provides the VFS with an updated node hash value based on the new directory
128 entry offset when a file is renamed. Not applicable in Haiku.
129 */
130 void
vfs_hash_rehash(struct vnode * vp,uint64 hash)131 vfs_hash_rehash(struct vnode* vp, uint64 hash)
132 {
133 return;
134 }
135